Capmatinib produced rapid, deep responses in patients with advanced non–small cell lung cancer (NSCLC) harboring MET exon 14 (METex14) skipping mutations, according to a presentation at the AACR virtual meeting I.
The duration of response was impressive in both treatment-naive and previously treated patients, according to presenter Edward B. Garon, MD, of the University of California, Los Angeles.
In view of these responses, Dr. Garon urged early molecular testing in NSCLC.
He also noted that capmatinib produced responses in patients with brain metastases. However, because of small patient numbers, additional study is needed to validate the intracranial efficacy of capmatinib and ascertain mechanisms of resistance.
Study Rationale and Details
Capmatinib is a highly selective, reversible, and potent inhibitor of MET tyrosine kinase that crosses the blood-brain barrier.
In the phase 2 GEOMETRY mono-1 study, Dr. Garon and colleagues tested capmatinib, given at 400 mg orally twice a day, in patients with METex14-mutated, ALK and EGFR wild-type, stage IIIB/IV NSCLC. Patients with neurologically stable or asymptomatic brain metastases were eligible.
Dr. Garon presented safety data for all patients enrolled in this study and efficacy data for patients in cohorts 4 and 5b. Cohort 4 enrolled patients who received prior systemic therapy for advanced disease, and cohort 5b enrolled treatment-naive patients. Both cohorts had METex14 gene mutations but not amplification.
There were 97 patients evaluable for efficacy – 69 previously treated and 28 treatment naive. The median age in both cohorts was 71 years, most patients were female (58% of previously treated and 64.3% of treatment-naive patients), and most were never-smokers (58% and 64.3%, respectively). Adenocarcinoma was the predominant histology.
The overall response rate, per an independent review committee, was 40.6% in previously treated patients and 67.9% in treatment-naive patients.
Waterfall plots showed deep responses, with only four cases of disease progression in the previously treated cohort and none in the treatment-naive cohort.
Responses occurred rapidly. Many responses exceeded 1 year and were ongoing at the data cut-off. The median response duration was 9.72 months in previously treated patients and 11.14 months in treatment-naive patients.
There were 13 patients with evaluable baseline brain metastases (3.3 brain lesions per patient [range, 1-8]). Twelve patients had intracranial disease control, and seven patients (54%) had intracranial response. Four patients had complete resolution of all brain lesions.
Intracranial responses were generally seen by the first radiologic evaluation and occurred as rapidly as systemic responses.
With safety data on all 334 patients in the trial, the GEOMETRY mono-1 study is the largest reported experience with capmatinib in NSCLC patients. The median treatment exposure time was 14.9 weeks.
Overall, 35.6% of patients experienced a grade 3/4 adverse event (AE). Grade 4 AEs were observed in 4.5% of patients, and there were no treatment-related deaths.
Peripheral edema (41.6%), nausea (33.2%), increased blood creatinine (19.5%), and vomiting (18.9%) were the most frequent AEs of any grade.
In all, 21.9% of patients required dose adjustments due to treatment-related AEs, and 11.1% of patients stopped treatment because of an AE.
This study was sponsored by Novartis. Dr. Garon disclosed relationships with Novartis, AstraZeneca, Bristol-Myers Squibb, Dracen, Dynavax, Eli Lilly, EMD Serono, Genentech, GSK, Iovance, Merck, Mirati, and Neon.
Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.
SOURCE: Garon EB et al. AACR 2020, Abstract CT082.
This story originally appeared on MDedge.com.